Consolidated Statements of Income - USD ($) shares in Thousands, $ in Thousands		12 Months Ended
		Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Revenues:
Rental income		$ 1,445,871	$ 1,648,815	$ 1,598,948
Resident fees and services		2,779,423	2,504,731	2,158,031
Interest income		73,811	97,963	84,141
Other income		17,536	29,651	18,706
Total revenues		4,316,641	4,281,160	3,859,826
Expenses:
Interest expense		484,622	521,345	492,169
Property operating expenses		2,083,925	1,876,983	1,622,257
Depreciation and amortization		921,720	901,242	826,240
General and administrative		122,008	155,241	147,416
Transaction costs		0	42,910	110,926
Loss (gain) on derivatives, net		2,284	(2,448)	(58,427)
Loss (gain) on extinguishment of debt, net		37,241	17,214	34,677
Provision for loan losses		62,966	10,215	0
Impairment of asset		124,483	37,207	2,220
Other expenses		177,776	11,998	46,231
Total expenses		4,017,025	3,571,907	3,223,709
Income from continuing operations before income taxes and income from unconsolidated entities		299,616	709,253	636,117
Income tax (expense) benefit		(20,128)	19,128	(6,451)
(Loss) income from unconsolidated entities		(83,125)	(10,357)	(21,504)
Income from continuing operations		196,363	718,024	608,162
Discontinued operations:
Gain (loss) on real estate dispositions, net		344,250	364,046	280,387
Net income		540,613	1,082,070	888,549
Less: Preferred stock dividends		49,410	65,406	65,406
Less: Preferred stock redemption charge		9,769	0	0
Net Income Loss Attributable To Noncontrolling Interest	[1]	17,839	4,267	4,799
Net income attributable to common stockholders		$ 463,595	$ 1,012,397	$ 818,344
Average number of common shares outstanding:
Basic		367,237	358,275	348,240
Diluted		369,001	360,227	349,424
Basic:
Income from continuing operations		$ 0.53	$ 2	$ 1.75
Net income attributable to common stockholders		1.26	2.83	2.35
Diluted:
Income from continuing operations		0.53	1.99	1.74
Net income attributable to common stockholders		$ 1.26	$ 2.81	$ 2.34

[1] Includes amounts attributable to redeemable noncontrolling interests